import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()) {
            try {
                int num1 = sc.nextInt();
                int num2 = sc.nextInt();
                System.out.println("sum = " + (num1 + num2));
            } catch (InputMismatchException e) {
                System.out.println("Incorrect input: two integer is required");
                 sc.nextLine();
            }
        }
    }
}